21214859 has 2 divisors, whose sum is σ = 21214860. Its totient is φ = 21214858.

The previous prime is 21214847. The next prime is 21214873. The reversal of 21214859 is 95841212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21214859 is a prime.

It is not a weakly prime, because it can be changed into another prime (21214889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10607429 + 10607430.

It is an arithmetic number, because the mean of its divisors is an integer number (10607430).

Almost surely, 2^21214859 is an apocalyptic number.

21214859 is a deficient number, since it is larger than the sum of its proper divisors (1).

21214859 is an equidigital number, since it uses as much as digits as its factorization.

21214859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 32.

The square root of 21214859 is about 4605.9590749376. The cubic root of 21214859 is about 276.8301469262.

The spelling of 21214859 in words is "twenty-one million, two hundred fourteen thousand, eight hundred fifty-nine".